Lightning arrester



June 2, 1942. N. FITGER 2,285,198

LIGHTNING ARRESTER Filed Aug. '7, 1940 Inventor.

Nicolai Fit er;

H Attorh ey Patented June 2, 1942 UNITED STATES PATENT OFFICE LIGHTNING ARRESTER tion of New York Application August 7, 1940, Serial No. 351,738 In Germany October 12, 1939 4 Claims.

This invention relates to lightning arresters, and more particularly to mounting arrangements for arc expulsion type arresters.

In the protection :of electrical transmission lines from over voltages such as lightning surges, it is advantageous to use arc expulsion type arresters because of their relatively low cost. With this type of arrester it is generally necessary to provide a special crossarm on the transmission line poles or towers to support the expulsion arrester tubes which are usually so mounted as to provide a small air gap between the end of the tube and the line conductor to be protected. Such special supporting means for the arrester tubes limit the economies which may otherwise be eifected by their use.

It is therefore an object of the present invention to provide a new and improved arc expulsion type lightning arerster and line supporting insulator arrangement which eliminates the necessity for a special crossarm support for the lightning arrester tubes.

For a consideration of what I .believe to be novel and my invention, attention is directed to the following description and the claims appended thereto taken in connection with the accompanying drawing, the single ligure of which is a cross sectional view of an insulator and an expulsion type lightning arrester arrangement constructed in accordance with the invention.

In the illustrated embodiment a transmission line conductor III is suitably tied to the cap of a pin type insulator Il which in turn is secured at its lower end by means of a suitable metal bracket I2 to a crossarm of a pole or tower (not shown). The insulator is provided with a longitudinal tubular passage I3 extending axially therethrough in which, according to the invention, a lightning arrester I4 is arranged coaxially with the insulator. The lightning arrester comprises a longitudinal tube I5 of insulating material having upper and lower electrodes it and I1, respectively, extending short distances into the opposite ends of the tube so as to insure that the arc strikes within the tube instead of exteriorly thereof over the outer surface of the tube. At least the inner wall of the tube is of hard ber or some other suitable material which upon the occurrence of an arc between the electrodes I6 and Il and consequent heating thereof, emits a large quantity of gas to expel the arc through an axial opening provided through the lower electrode for that purpose. The lightning arrester is secured at its lower electrode I'I which extends beyond the lower end 55 of the insulator by a metallic supporting member or arm I8 to the bracket I2 and is grounded therethrough. The upper electrode I6 of the lightning arrester is spacedv by a suitable gap from an electrode I9 closing the upper end of the passage I3 ofthe insulator and connected by lead 2U to the conductor I0. The gap spacing may be varied by selecting the proper thickness for the washers 22 between the support I8 and bracket I2 which removably or adjustably supports the arm I8.

While in the illustrated embodiment I have shown the lightning arrester tube I5 arranged coaxially Within the passage I3 of the insulator and spaced from the` adjacent walls thereof, it will be readily understood that such spacing is not essential to the practice of the invention,

It will be obvious that I have provided an arrangement of a lightning arrester of the expulsion tube type and an insulator for supporting the line to be protected which is of a simple, compact design and eliminates the necessity for separate crossarms or other costly supporting means for the lightning arrester tubes. The ararrester and insulator may be assembled and calibrated in the factory for the particular line voltage to be protected while the lield installation involves only the mounting of the single unit. Faulty mounting of the arrester is thereby precluded while at the same time it is readily accessible for inspection or replacement.

Having described the principle of operation of my invention in what I consider to represent a preferred embodiment, I desire to have it understood that the speciiic arrangement shown is merely illustrative and that the invention may be carried out in other ways.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination with an insulator for supporting at one end a line to be protected against over voltages and having a longitudinal opening therethrough, a lightning arrester arranged within said opening and having electrodes at opposite ends, one end electrode being spaced by a gap from said line, a bracket member for supporting said insulator, an arm removably supported by said bracket and being grounded therethrough, the opposite end electrode of said lightning arrester being supported by said arm so as to maintain said lightning arrester in a predetermined spaced relationship relative to said insulator and to provide a grounding connection to said opposite end electrode.

2. In combination with an insulator for supporting at one end a line to be protected against over voltages and having a longitudinal passage extending axially therethrough, a support for the opposite end of said insulator, an electrode closing the line end of said passage and electrically connected to said line, an arc expulsion tube type lightning arrester arranged coaxially within said lpassage, an arm mounted on said insu-v lator support, the line end of said lightning ar-r rester being spaced fromY said insulator electrode, and means for removably mounting the lower end of said lightning arrester on said arm so as to facilitate replacement of said arrester.

3. In combination with an insulator for sup,- porting at its upper end a line to be protected against over voltages, and having an axially extending passage therethrough, said insulator being provided with an electrode at the line end of said passage and connected to the line, an arc expulsion lightning arrester tube having upper and lower electrodes, a bracket member for supporting said insulator, an arm removably supported by said bracket, and means including said arm for removably mounting said arrester coaxially Within said passage and spaced from the walls of said passage, said upper electrode being spaced from said insulator electrode, and said lower electrode having an arc expulsion opening beyond the lower end of said insulator.

4. In combination with an insulator for supporting at one end a line to be protected against over voltages and having a longitudinal passage extending therethrough, an electrode arranged within the line end of said passage substantially closing same and connected to said line, a metallic bracket supporting the opposite end of said insulator, an arc expulsion tube type lightning arrester having upper and lower electrodes, an arm removably supported by said bracket, and means for removably securing said arm to said lower electrode for supporting said arrester Vcoaxially within said passage and spaced from the Walls thereof, the lightning arrester electrode nearest said line being spaced by a gap from said insulator electrode, and means for grounding said lower electrode through said bracket, said lower electrode having an arc expulsion opening therethrough.

` NICOLAI FITGER. 

